1. Field of the Invention
The present invention relates to a mirror fixing structure for an optical pickup, in which a half mirror and a total reflection mirror are set in predetermined locations in the optical pickup so that the half mirror and the total reflection mirror are fixed in a manner to be prevented from coming off.
2. Description of the Related Art
In a conventional mirror fixing structure for an optical pickup, a half mirror is fixed by a spring and a total reflection mirror is fixed by another spring, or temporarily fixed with an adhesive.
Therefore, there is caused a problem that two springs are necessary and a working process of fixing a total reflection mirror is necessary in addition to the working process of fixing a half mirror, which lead to an increase in working processes.
A first prior art is shown in FIGS. 9 and 10. A pair of right and left grooves 111 communicated to an opening 102a of a light passing hole 102 are formed on both sides of an inner side 105c among four inner sides 105a to 105d of a light passing hole 102, the inner side 105c being opposed to an inner part side 103c of a half mirror 103, both side edges of a fixture body 112a of a leaf-spring fixture 112 are inserted into the both grooves 111, a pair of right and left presser plates 112b are provided to extend from the both side edges of the fixture body 112a to elastically abut against a surface of the half mirror 103, a pair of right and left engaging pawls 112c are bent from the both side edges of the fixture body 112a in a direction opposed to a direction, in which the presser plates 112b extend, to engage with the inner side 105c, and a latch piece 112d are bent from a center of the fixture body 112a in the same direction as that of the engaging pawls 112c to extend to a peripheral edge of the opening 102a of the light passing hole 102 (see, for example, JP-A-2002-230809).
However, the single half mirror 103 in this structure is fixed only by the leaf-spring fixture 112.
A second prior art is shown in FIGS. 11, 12A and 12B. A half mirror 202 is supported by mirror holding pieces 206, and closely fixed to a mirror bonding and holding surface 207a by means of an adhesive 209 and to a mirror abutting and holding surface 207b by means of a spring 208. A groove 210 is provided on the mirror bonding and holding surface 207a that fixes the half mirror 202 thereto (see, for example, JP-A-8-111027).
However, the half mirror 202 in this structure is fixed only by the spring 208.